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Updated: Jun 25, 2026
08:51
Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks
Published on: May 13, 2016
Variable progress toward ecological speciation in parapatry: stickleback across eight lake-stream transitions
Daniel Berner1, Anne-Catherine Grandchamp, Andrew P Hendry
1Zoological Institute, University of Basel, CH-4051 Basel, Switzerland. Daniel.berner@unibas.ch
Evolution; International Journal of Organic Evolution
|February 21, 2009
Summary
Ecological speciation in threespine stickleback fish shows variation across lake-stream transitions. Strong selection and limited dispersal promote adaptive divergence and reproductive isolation, even with gene flow.
Area of Science:
- Evolutionary biology
- Speciation research
- Ecology
Background:
- Divergent selection across habitats can drive adaptive divergence and reproductive isolation.
- Ecological speciation is a key process in evolutionary biology, explaining how new species arise.
- Threespine stickleback fish provide a model system for studying rapid adaptation and speciation.
Purpose of the Study:
- To examine the variation in ecological speciation progress in threespine stickleback fish.
- To investigate the role of habitat transitions and divergent selection in adaptive divergence.
- To understand the genetic and ecological factors influencing reproductive isolation.
Main Methods:
- Quantified stickleback diets to identify habitat use and ecotones.
- Measured genetically based phenotypes related to foraging morphology.
- Analyzed neutral genetic markers (microsatellites) to assess population structure and gene flow.
- Employed coalescent-based simulations to infer divergence history.
Main Results:
- Lake-stream transitions frequently coincide with limnetic-benthic ecotones, driving adaptive divergence in foraging morphology.
- Adaptive divergence is often linked to reproductively isolated parapatric populations.
- Populations appear to have diverged with gene flow within a few thousand generations.
- Significant variation exists in the progress toward ecological speciation across different transitions.
Conclusions:
- Ecological speciation can occur in a parapatric context, driven by divergent selection and limited dispersal.
- The outcome of ecological speciation varies considerably among populations.
- Habitat transitions and associated ecotones are critical in initiating adaptive divergence and reproductive isolation.
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